A mutation in the low-complexity domain of splicing factor hnRNPA1 linked to amyotrophic lateral sclerosis disrupts distinct neuronal RNA splicing networks.

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disease characterized by loss of motor neurons. Human genetic studies have linked mutations in RNA-binding proteins as causative for this disease. The hnRNPA1 protein, a known pre-mRNA splicing factor, is mutated in some ALS patients. Here, two human cell models were generated to investigate how a mutation in the C-terminal low-complexity domain (LCD) of hnRNPA1 can cause splicing changes of thousands of transcripts that collectively are linked to the DNA damage response, cilium organization, and translation. We show that the hnRNPA1 D262V mutant protein binds to new binding sites on differentially spliced transcripts from genes that are linked to ALS. We demonstrate that this ALS-linked hnRNPA1 mutation alters normal RNA-dependent protein-protein interactions. Furthermore, cells expressing this hnRNPA1 mutant exhibit a cell aggregation phenotype, markedly reduced growth rates, changes in stress granule kinetics, and aberrant growth of neuronal processes. This study provides insight into how a single amino acid mutation in a splicing factor can alter RNA splicing networks of genes linked to ALS.

Coordinate regulation of alternative pre-mRNA splicing events by the human RNA chaperone proteins hnRNPA1 and DDX5.

Alternative premessenger RNA (pre-mRNA) splicing is a post-transcriptional mechanism for controlling gene expression. Splicing patterns are determined by both RNA-binding proteins and nuclear pre-mRNA structure. Here, we analyzed pre-mRNA splicing patterns, RNA-binding sites, and RNA structures near these binding sites coordinately controlled by two splicing factors: the heterogeneous nuclear ribonucleoprotein hnRNPA1 and the RNA helicase DDX5. We identified thousands of alternative pre-mRNA splicing events controlled by these factors by RNA sequencing (RNA-seq) following RNAi. Enhanced cross-linking and immunoprecipitation (eCLIP) on nuclear extracts was used to identify protein-RNA-binding sites for both proteins in the nuclear transcriptome. We found a significant overlap between hnRNPA1 and DDX5 splicing targets and that they share many closely linked binding sites as determined by eCLIP analysis. In vivo SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension) chemical RNA structure probing data were used to model RNA structures near several exons controlled and bound by both proteins. Both sequence motifs and in vivo UV cross-linking sites for hnRNPA1 and DDX5 were used to map binding sites in their RNA targets, and often these sites flanked regions of higher chemical reactivity, suggesting an organized nature of nuclear pre-mRNPs. This work provides a first glimpse into the possible RNA structures surrounding pre-mRNA splicing factor-binding sites.

Patterns in the Reporting of Aggressive Histologic Subtypes in Papillary Thyroid Cancer.

INTRODUCTION: The tall cell, columnar, and diffuse sclerosing subtypes are aggressive histologic subtypes of papillary thyroid cancer (PTC) with increasing incidence, yet there is a wide variation in reporting. We aimed to identify and compare factors associated with the reporting of these aggressive subtypes (aPTC) to classic PTC (cPTC) and secondarily identify differences in outcomes. METHODS: The National Cancer Database was utilized to identify cPTC and aPTC from 2004 to 2017. Patient and facility demographics and clinicopathologic variables were analyzed. Independent predictors of aPTC reporting were identified and a survival analysis was performed. RESULTS: The majority of aPTC (67%) were reported by academic facilities. Compared to academic facilities, all other facility types were 1.4-2.0 times less likely to report aPTC (P < 0.05). Regional variation in reporting was noted, with more cases reported in the Middle Atlantic, despite there being more total facilities in the South Atlantic and East North Central regions. Compared to the Middle Atlantic, all other regions were 1.4-5 times less likely to report aPTC (P < 0.001). Patient characteristics including race and income were not associated with aPTC reporting. Compared to cPTC, aPTC had higher rates of aggressive features and worse 5-y overall survival (90.5% versus 94.5%, log rank P < 0.001). CONCLUSIONS: Aggressive subtypes of PTC are associated with worse outcomes. Academic and other facilities in the Middle Atlantic were more likely to report aPTC. This suggests the need for further evaluation of environmental or geographic factors versus a need for increased awareness and more accurate diagnosis of these subtypes.

Perineural Invasion in Papillary Thyroid Cancer: A Rare Indicator of Aggressive Disease.

BACKGROUND: Perineural invasion (PNI) is associated with aggressive tumor behavior, increased locoregional recurrence, and decreased survival in many carcinomas. However, the significance of PNI in papillary thyroid cancer (PTC) is incompletely characterized. METHODS: Patients diagnosed with PTC and PNI from 2010-2020 at a single, academic center were identified and matched using a 1:2 scheme to patients without PNI based on gross extrathyroidal extension (ETE), nodal metastasis, positive margins, and tumor size (±4 cm). Mixed and fixed effects models were used to analyze the association of PNI with extranodal extension (ENE)-a surrogate marker of poor prognosis. RESULTS: In total, 78 patients were included (26 with PNI, 52 without PNI). Both groups had similar demographics and ultrasound characteristics preoperatively. Central compartment lymph node dissection was performed in most patients (71%, n = 55), and 31% (n = 24) underwent a lateral neck dissection. Patients with PNI had higher rates of lymphovascular invasion (50.0% vs. 25.0%, p = 0.027), microscopic ETE (80.8% vs. 44.0%, p = 0.002), and a larger burden [median 5 (interquartile range [IQR] 2-13) vs. 2 (1-5), p = 0.010] and size [median 1.2 cm (IQR 0.6-2.6) vs. 0.4 (0.2-1.4), p = 0.008] of nodal metastasis. Among patients with nodal metastasis, those with PNI had an almost fivefold increase in ENE [odds ratio [OR] 4.9 (95% confidence interval [CI] 1.5-16.5), p = 0.008] compared with those without PNI. More than a quarter (26%) of all patients had either persistent or recurrent disease over follow-up (IQR 16-54 months). CONCLUSIONS: PNI is a rare, pathologic finding that is associated with ENE in a matched cohort. Additional investigation into PNI as a prognostic feature in PTC is warranted.

Treatment of Secondary Hyperparathyroidism and Posttransplant Tertiary Hyperparathyroidism.

INTRODUCTION: Secondary hyperparathyroidism (sHPT) is prevalent in dialysis patients and can lead to tertiary hyperparathyroidism (tHPT) after kidney transplantation. We aimed to assess the association of pretransplant sHPT treatment on posttransplant outcomes. METHODS: We reviewed kidney transplant patients treated with parathyroidectomy or cinacalcet for sHPT. We compared patients biochemical and clinical parameters, and outcomes based on sHPT treatment. RESULTS: A total of 41 patients were included: 18 patients underwent parathyroidectomy and 23 patients received cinacalcet prior to transplantation. There were no significant differences between demographics, comorbidities, allograft characteristics or pre-sHPT intervention parathyroid hormone (PTH) and calcium levels. Patients that underwent parathyroidectomy were on dialysis for longer, although not significantly (71.9 versus 42.3 mo, P = 0.051). At time of transplantation, patients treated by parathyroidectomy had increased rates of controlled sHPT (88.9%; 16/18 versus 47.8%; 11/23, P = 0.008). Patients treated by parathyroidectomy had decreased development of tHPT (5.9%; 1/17; versus 42.1%; 8/19, P = 0.020) as well as decreased rates of posttransplant treatment with cinacalcet (11.1%; 2/18 versus 52.2%; 12/23, P = 0.008). Three patients treated with cinacalcet underwent parathyroidectomy after transplantation. Median PTH after transplant remained lower in patients treated by parathyroidectomy prior to transplant compared to those treated with cinacalcet (60.7 [interquartile range 39.7-133.4] versus 170.0 [interquartile range 128.4-292.7], P = 0.001). Allograft function and survival were similar for parathyroidectomy and cinacalcet, with median follow-up after transplantation of 56.7 and 34.2 mo, respectively. CONCLUSIONS: sHPT treated by parathyroidectomy is associated with controlled PTH levels at transplantation and decreased rates of tHPT. Long-term outcomes should be studied on a larger scale.

Passing The Scalpel: A Student Initiative in Identifying and Addressing Unmet Needs in Dental Education.

PURPOSE: Becoming an oral-maxillofacial surgeon is often challenging for young trainees. The purpose of this manuscript is to explore how a student-led group, which emphasizes networking, mentorship, and academic opportunities, may impact one's journey to becoming an oral-maxillofacial surgeon. PATIENTS AND METHODS: This was a cross-sectional descriptive study where a 5-question Likert-type survey was administered to students who matriculated into residency and participated in a student-led group called Passing The Scalpel (PTS). This survey evaluated the value of PTS in providing exposure, career decision-making, networking/mentorship, and camaraderie. The results were analyzed, and statistical outcomes were evaluated. RESULTS: There was an 80.5% response rate (n = 29). Question 1 regarding first exposure to oral-maxillofacial surgery had a mean score of 2.55 (standard deviation [SD] = 1.35; χ2 = 15.39; P < .05). Question 2 regarding choosing oral-maxillofacial surgery as a career had a mean score of 3.66 (SD = 1.11; χ2 = 10.84; P < .05). Question 3 regarding offering mentorship and networking had a mean score of 4.14 (SD = 0.92; χ2 = 27.81; P < .05). Question 4 regarding increasing applicant camaraderie had a mean score of 4.21 (SD = 0.77; χ2 = 36.71; P < .05). Question 5 regarding the importance of PTS within a dental curriculum had a score of 4.48 (SD = 0.68; χ2 = 41.89; P < .05). CONCLUSION: PTS is an effective student-led initiative that emphasizes early exposure, networking, and mentorship opportunities and encourages students in choosing oral-maxillofacial surgery as a specialty. PTS demonstrates that student-led initiatives can fulfill unmet needs in the dental curriculum.

Evaluating the Safety of the Hand Surgery Procedure Room: A Single-Center Cohort of 1,404 Surgical Encounters.

PURPOSE: Performing hand surgeries in the procedure room (PR) setting instead of the operating room effectively reduces surgical costs. Understanding the safety or complication rates associated with the PR is important in determining the value of its use. Our purpose was to describe the incidence of medical and surgical complications among patients undergoing minor hand surgeries in the PR. METHODS: We retrospectively reviewed all adult patients who underwent an operation in the PR setting between December 2013 and May 2019 at a single tertiary academic medical center by 1 of 5 fellowship-trained orthopedic hand surgeons. Baseline patient characteristics were described. Complication rates were obtained via chart review. RESULTS: For 1,404 PR surgical encounters, 1,796 procedures were performed. Mean patient age was 59 ± 15 years, 809 were female (57.6%), and average follow-up was 104 days. The most common surgeries were carpal tunnel release (39.9%), trigger finger release (35.9%), and finger mass or cyst excision (9.6%). Most surgeries were performed using a nonpneumatic wrist tourniquet (58%), whereas 42% used no tourniquet. No patient experienced a major medical complication. No procedure was aborted owing to intolerance. No patient required admission. No intraoperative surgical or medical complications occurred. Observed complications included delayed capillary refill requiring phentolamine administration after a trigger thumb release performed using epinephrine without a tourniquet (n = 1; 0.1%), complex regional pain syndrome (n = 3; 0.2%), infection requiring surgical debridement (n = 2; 0.2%), and recurrent symptoms requiring reoperation (n = 8; 0.7%). CONCLUSIONS: In this cohort of patients in whom surgery was performed in a PR, there were no major intraoperative surgical or medical complications. There was a low rate of postoperative infection, development of complex regional pain syndrome, and a low need for revision surgery. These observations do not support the concern for safety as a barrier to performing minor hand surgery in the PR setting. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

PD-L1 expression and infiltration by CD4+ and FoxP3+ T cells are increased in Xp11 translocation renal cell carcinoma and indicate poor prognosis.

AIMS: Interaction between programmed death-1 ligand (PD-L1) and its receptor programmed death 1 (PD-1) on T cells inactivates antitumour immune responses. PD-L1 expression has been associated with poor prognosis in renal cell carcinoma (RCC) and predicts adverse outcome. This study was designed to evaluate the impact of PD-L1 expression and the immune microenvironment on the clinical outcome in Xp11 translocation renal cell carcinoma (TRCC) and, therefore, their potential relevance as prognostic biomarkers. METHODS AND RESULTS: The present retrospective analysis investigated expression of PD-L1 and immune cells CD8, CD4, CD3, forkhead box protein 3 (FoxP3) and PD-1 in TRCC compared to other types of RCC. FFPE specimens were collected between 2011 and 2017 from 311 patients who underwent nephrectomy at our institution for RCC. Specimens were immunostained for PD-L1, CD8, CD4, CD3, FoxP3 and PD-1, and an outcome analysis was conducted. PD-L1 expression rate was highest in TRCC (68%, 16 of 25), followed by mucinous tubular and spindle cell RCC and collecting duct carcinoma (33%, one of three), papillary RCC (27%, seven of 26), clear cell RCC (16%, 29 of 233), chromophobe RCC (11%, two of 18) and multilocular cystic RCC (0%, none of three). In TRCC, PD-L1 expression was associated with poor recurrence-free survival (RFS) (P = 0.041). The CD4high and FoxP3high groups showed a significantly shorter RFS (P = 0.05 and P = 0.031, respectively) compared to CD4low and FOXPlow groups. CONCLUSION: PD-L1 expression was higher in TRCC than in other types of RCC. High PD-L1 tumour cell expression and tumour infiltration by CD4+ and FoxP3+ immune cells were associated with poor RFS in TRCC.

Wound-healing effect of adipose stem cell-derived extracellular matrix sheet on full-thickness skin defect rat model: Histological and immunohistochemical study.

The potential use of extracellular matrix (ECM) as a source of wound dressing material has recently received much attention. The ECM is an intricate network of various combinations of elastin, collagens, laminin, fibronectin, and proteoglycans that play a key role in stimulating cell proliferation and differentiation. We evaluated the efficacy of an ECM sheet derived from human adipose tissue as a wound dressing material to enhance healing. We prepared a novel porous ECM sheet dressing scaffold from human adipose tissue. in vitro analysis of the ECM sheets showed efficient decellularisation; absence of immunostimulatory components; and the presence of a wide number of angiogenic and bioactive factors, including collagen, elastin, and proteoglycans. To evaluate in vivo efficacy, full-thickness excisional wounds were created on the dorsal skin of a rat, and the ECM sheets; secondary healing foam wound dressing, Healoderm; or a conventional dressing were applied to each wound site. Photographs were taken every other day, and the degree of reepithelialisation of the wounds was determined. Application of an ECM sheet dressing enhanced the macroscopic wound-healing rate on days 4, 7, and 10 compared with that in the control group. Microscopic analysis indicated that the reepithelialisation rate of the wound was higher in the ECM group compared with that in the control group; the reepithelialisation rate was better than that of the secondary healing foam wound dressing. Moreover, a denser and more organised granulation tissue was formed in the ECM sheet group compared with that in the secondary healing foam wound dressing and control groups. The ECM sheet also showed the highest microvessel density compared with the secondary healing foam wound dressing and control groups. Based on these data, we suggest that a bioactive ECM sheet dressing derived from human adipose can provide therapeutic proteins for wound healing.

Switching to tenofovir vs continuing entecavir for hepatitis B virus with partial virologic response to entecavir: a randomized controlled trial.

Entecavir 0.5 mg (ETV) is widely used among treatment-naïve chronic hepatitis B (CHB) patients. However, 10%-30% of patients show partial virologic response (PVR) to the drug. If the hepatitis B virus (HBV) continues to replicate, the underlying liver disease may progress. Herein, we compared the efficacy of switching to tenofovir disoproxil fumarate (TDF) with that of continuing ETV in CHB patients with PVR to ETV. This was an open-label randomized controlled trial including CHB patients who had been receiving 0.5 mg of ETV for >12 months, but who still had detectable HBV DNA levels of >60 IU/mL without known resistance to ETV. Sixty patients were enrolled and 45 qualified for the study: Twenty-two patients were randomly assigned into the TDF group and 23 into the ETV group. After 12 months of treatment, the virologic response rate (HBV DNA <20 IU/mL) was significantly higher in the TDF group than in the ETV group, as measured using per-protocol analysis (55% vs 20%; P = .022) and intention-to-treat analysis (50% vs 17.4%; P = .020). The reduction in HBV DNA was greater (-1.13 vs -0.67 log10 IU/mL; P = .024), and the mean HBV DNA level was lower (1.54 vs 2.01 log10 IU/mL; P = .011) in the TDF group than in the ETV group. In conclusion, to achieve optimal response in CHB patients with PVR to ETV, switching to TDF would be a better strategy than continuing ETV. Appropriate modification of therapy would further improve the outcome of chronic HBV infection.

Efficient CRISPR-rAAV engineering of endogenous genes to study protein function by allele-specific RNAi.

Gene knockout strategies, RNAi and rescue experiments are all employed to study mammalian gene function. However, the disadvantages of these approaches include: loss of function adaptation, reduced viability and gene overexpression that rarely matches endogenous levels. Here, we developed an endogenous gene knockdown/rescue strategy that combines RNAi selectivity with a highly efficient CRISPR directed recombinant Adeno-Associated Virus (rAAV) mediated gene targeting approach to introduce allele-specific mutations plus an allele-selective siRNA Sensitive (siSN) site that allows for studying gene mutations while maintaining endogenous expression and regulation of the gene of interest. CRISPR/Cas9 plus rAAV targeted gene-replacement and introduction of allele-specific RNAi sensitivity mutations in the CDK2 and CDK1 genes resulted in a >85% site-specific recombination of Neo-resistant clones versus ∼8% for rAAV alone. RNAi knockdown of wild type (WT) Cdk2 with siWT in heterozygotic knockin cells resulted in the mutant Cdk2 phenotype cell cycle arrest, whereas allele specific knockdown of mutant CDK2 with siSN resulted in a wild type phenotype. Together, these observations demonstrate the ability of CRISPR plus rAAV to efficiently recombine a genomic locus and tag it with a selective siRNA sequence that allows for allele-selective phenotypic assays of the gene of interest while it remains expressed and regulated under endogenous control mechanisms.

Inducible Nitric Oxide Synthase Polymorphisms and Nitric Oxide Levels in Individuals with Chronic Periodontitis.

This study aimed to investigate whether the -1026(A>C)(rs2779249) and +2087(A>G)(2297518) polymorphisms in the NOS2 gene were associated with chronic periodontitis (CP) and with salivary levels of nitrite (NO2-) and/or nitrate + nitrite (NOx). A group of 113 mixed-race patients were subjected to periodontal, genetic, and biochemical evaluations (65 CP/48 periodontally healthy subjects). DNA was extracted from oral epithelial cells and used for genotyping by polymerase chain reaction (real-time). Salivary NOx concentrations were determined using an ozone-based chemiluminescence assay. Association of CP with alleles and genotypes of the -1026(A>C) polymorphism was found (X² test, p = 0.0075; 0.0308), but this was not maintained after multiple logistic regression, performed to estimate the effect of covariates and polymorphisms in CP. This analysis demonstrated, after correction for multiple comparisons, that only the female gender was significantly associated with CP. Polymorphisms analyzed as haplotypes were not associated with CP. NOx levels were significantly higher in the control group of heterozygous individuals for both polymorphisms. In conclusion, the female gender was significantly associated with CP, and higher levels of salivary NOx were found in control subjects and associated with the heterozygous state of the NOS2 polymorphisms, reinforcing the potential of NO metabolites as markers of periodontitis status.

Regional and seasonal differences in skin irritation and neurosensitivity in Chinese and South Korean women.

BACKGROUND: China has a great variety of geographical and climatic conditions, and several cultural differences exist within the country; thus, understanding the regional and seasonal differences that cause skin sensitivities in this country is important. OBJECTIVE: The aim of this study was to assess skin sensitivity of women from six cities in China and from South Korea during the winter and summer seasons to aid the development of suitable and effective dermatological products. METHODS: This multicentre study included 754 healthy female volunteers, and was conducted in the winter (between January and March) and summer (between June and July) of 2011. Patch tests were performed using 0.5% sodium lauryl sulphate (SLS) aqueous solution and 0.15% retinol in 1,3-butylene glycol on the back of the volunteers. Simultaneously, stinging tests were performed on their cheeks by using 5% lactic acid solution and 0.001% capsaicin solution, each in a negative control vehicle (distilled water and 10% ethanol solution, respectively). RESULTS: The patch test results showed that the subjects in Beijing and Shenyang were more sensitive to SLS, retinol and lactic acid in the winter than were those in Guangzhou, Shanghai, Wuhan, Chengdu and South Korea. The stinging test results revealed that the subjects in Beijing were more neurosensitive to lactic acid in the winter; however, during the same season, the subjects from Shanghai and Guangzhou were significantly more neurosensitive to capsaicin. CONCLUSION: Our observations indicate that skin sensitivity differs considerably between women from different parts of China and South Korea. We recommend that these differences be considered during the development of cosmetic products in these countries.

Morphology, physiological characteristics, and complete sequence of marine bacteriophage ϕRIO-1 infecting Pseudoalteromonas marina.

Bacteria of the genus Pseudoalteromonas are ubiquitous in the world's oceans. Marine bacteria have been posited to be associated with a major ancient branch of podoviruses related to T7. Yet, although Pseudoalteromonas phages belonging to the Corticoviridae and the Siphoviridae and prophages belonging to the Myoviridae have been reported, no Pseudoalteromonas podovirus was previously known. Here, a new lytic Pseudoalteromonas marina phage, ϕRIO-1, belonging to the Podoviridae was isolated and characterized with respect to morphology, genomic sequence, and biological properties. Its major encoded proteins were distantly similar to those of T7. The most similar previously sequenced viruses were Pseudomonas phage PA11 and Salinivibrio phage CW02. Whereas many elements of the morphology and gene organization of ϕRIO-1 are similar to those of podoviruses broadly related to T7, ϕRIO-1 conspicuously lacked an RNA polymerase gene. Since definitions of a T7 supergroup have included similarity in the DNA polymerase gene, a detailed phylogenetic analysis was conducted, and two major DNA polymerase clades in Autographivirinae and several structural variants of the polA family represented in podoviruses were found. ϕRIO-1 carries an operon similar to that in a few other podoviruses predicted to specify activities related to γ-glutamyl amide linkages and/or unusual peptide bonds. Most growth properties of ϕRIO-1 were typical of T7-like phages, except for a long latent period.

Exotic magnetism on the quasi-fcc lattices of the d3 double Perovskites La2NaB'O6 (B'=Ru, Os).

We find evidence for long-range and short-range (ζ=70 Å at 4 K) incommensurate magnetic order on the quasi-face-centered-cubic (fcc) lattices of the monoclinic double perovskites La2NaRuO6 and La2NaOsO6, respectively. Incommensurate magnetic order on the fcc lattice has not been predicted by mean field theory, but may arise via a delicate balance of inequivalent nearest neighbor and next nearest neighbor exchange interactions. In the Ru system with long-range order, inelastic neutron scattering also reveals a spin gap Δ âˆ¼ 2.75 meV. Magnetic anisotropy is generally minimized in the more familiar octahedrally coordinated 3d3 systems, so the large gap observed for La2NaRuO6 may result from the significantly enhanced value of spin-orbit coupling in this 4d(3) material.

Forced collapse of the blastocoel cavity improves developmental potential in cryopreserved bovine blastocysts by slow-rate freezing and vitrification.

This study was conducted to evaluate the effectiveness of forced collapse of the blastocoel before slow-rate freezing and vitrification of bovine blastocysts. Cryopreservation of bovine blastocysts has been proposed as a tool to improve the feasibility of cattle production using the embryo transfer technique. However, the low efficiency of frozen-thawed embryos survival and further development is a crucial problem. In this study, bovine in vitro and in vivo blastocysts were slow-rate frozen and vitrified after forced blastocoele collapse (FBC) of the blastocyst cavity by puncturing the blastocoele with a pulled Pasteur pipet. Differences in the developmental potential of frozen-thawed blastocysts derived from FBC and non-FBC groups were found in both slow-rate freezing and vitrification. Furthermore, we found that the total cell number of blastocysts in FBC groups was increased and the index of apoptosis in FBC groups was decreased. Consistent with these results, real-time RT-PCR analysis data showed that expression of the anti-apoptotic Bcl-XL gene was significantly increased by FBC groups, whereas expression of the pro-apoptotic Bax gene was significantly decreased by FBC groups. Our results also showed that pregnancy outcomes in both slow-rate frozen and vitrified bovine in vivo blastocysts could be improved by reducing the fluid content after FBC of the blastocyst cavity. Therefore, we suggest that FBC of the blastocyst cavity with a pulled Pasteur pipet is an effective pre-treatment technique for both slow-rate freezing and vitrification of bovine blastocysts.

Low Mitotic Activity in Papillary Thyroid Cancer: A Marker for Aggressive Features and Recurrence.

CONTEXT: The significance of low mitotic activity in papillary thyroid cancer (PTC) is largely undefined. OBJECTIVE: We aimed to determine the behavioral landscape of PTC with low mitotic activity compared to that of no- and high-mitotic activity. METHODS: A single-institution consecutive series of PTC patients from 2018-2022 was reviewed. Mitotic activity was defined as no mitoses, low (1-2 mitoses/2 mm2) or high (≥3 mitoses/2 mm2) per the World Health Organization. The 2015 American Thyroid Association risk stratification was applied to the cohort, and clinicopathologic features were compared between groups. For patients with ≥6 months follow-up, Cox regression analyses for recurrence were performed. RESULTS: 640 PTCs were included - 515 (80.5%) no mitotic activity, 110 (17.2%) low mitotic activity, and 15 (2.3%) high mitotic activity. Overall, low mitotic activity exhibited rates of clinicopathologic features including vascular invasion, gross extrathyroidal extension, and lymph node metastases in between those of no- and high-mitotic activity. PTCs with low mitotic activity had higher rates of intermediate- and high-risk ATA risk stratification compared to those with no mitotic activity (p < 0.001). Low mitotic activity PTCs also had higher recurrence rates (15.5% vs. 4.5%, p < 0.001). Low mitotic activity was associated with recurrence, independent of the ATA risk stratification (HR 2.96; 95% CI 1.28-6.87, p = 0.01). CONCLUSIONS: Low mitotic activity is relatively common in PTC and its behavior lies within a spectrum between no- and high-mitotic activity. Given its association with aggressive clinicopathologic features and recurrence, low mitotic activity should be considered when risk stratifying PTC patients for recurrence.

Radioactive iodine administration is not associated with improved disease-specific survival in classic papillary thyroid carcinoma greater than 4 cm confined to the thyroid.

BACKGROUND: We aimed to evaluate the impact of radioactive iodine on disease-specific survival in intrathyroidal (N0M0) papillary thyroid carcinoma >4 cm, given conflicting data in the American Thyroid Association guidelines regarding their management. METHODS: The Surveillance, Epidemiology, and End Results database was queried for N0M0 classic papillary thyroid carcinoma >4 cm. Kaplan-Meier estimates were performed to compare disease-specific survival between radioactive iodine-treated and untreated groups. A multivariable Cox regression was performed to identify predictors of disease-specific survival. RESULTS: There were more patients aged ≥55 (41.7% vs 32.3%, P = .001) and fewer multifocal tumors (25.3% vs 30.6%, P = .006) in the no radioactive iodine group. Ten-year disease-specific survival was similar between the radioactive iodine treated and untreated groups (97.2% vs 95.6%, P = .34). Radioactive iodine was not associated with a significant disease-specific survival benefit (adjusted hazard ratio = 0.78, confidence interval [0.39-1.58], P = .49). Age ≥55 (adjusted hazard ratio = 3.50, confidence interval [1.69-7.26], P = .001) and larger tumor size (adjusted hazard ratio = 1.04, confidence interval [1.02-1.06], P < .001) were associated with an increased risk of disease-specific death. Subgroup analyses did not demonstrate improved disease-specific survival with radioactive iodine in patients ≥55 and in tumors >5 cm. CONCLUSION: Adjuvant radioactive iodine administration in classic papillary thyroid carcinoma >4 cm confined to the thyroid did not significantly impact disease-specific survival. Thus, these patients may not require routine treatment with adjuvant radioactive iodine.

Clinical utility of a microRNA classifier in cytologically indeterminate thyroid nodules with RAS mutations: A multi-institutional study.

BACKGROUND: Molecular testing guides the management of cytologically indeterminate thyroid nodules. We evaluated the real-world clinical benefit of a commercially available thyroid mutation panel plus microRNA risk classifier in classifying RAS-mutated nodules. METHODS: We performed a subgroup analysis of the results of molecular testing of Bethesda III/IV nodules using the ThyGenX/ThyGeNEXT-ThyraMIR platform at 3 tertiary-care centers between 2017 and 2021, defining a positive result as 10% or greater risk of malignancy. RESULTS: We identified 387 nodules from 375 patients (70.7% female, median age 59.3 years) who underwent testing. Positive nodules (32.3%) were associated with increased surgical intervention (74.4% vs 14.9%, P < .0001) and carcinoma on surgical pathology (46.4% vs 3.4%, P < .0001) compared to negative modules. RAS mutations were the most common mutations, identified in 71 of 380 (18.7%) nodules, and were classified as ThyraMIR- (28 of 71; 39.4%) or ThyraMIR+ (43 of 71; 60.6%). Among RAS-mutated nodules, there was no significant difference in operative rate (P = .2212) or carcinoma diagnosis (P = .6277) between the ThyraMIR+ and ThyraMIR- groups, and the sensitivity, specificity, negative predictive value, and positive predictive value of ThyraMIR were 64.7%, 34.8%, 40.0%, and 59.5%, respectively. CONCLUSION: Although testing positive is associated with malignancy in surgical pathology, the ThyraMIR classifier failed to differentiate between benign and malignant RAS-mutated nodules. Diagnostic lobectomy should be considered for RAS-mutated nodules, regardless of microRNA expression status.